The Avid CPS Disc Brake Adapter is used for mounting Avid Disc Brakes to 51mm International Standard (IS) or 74mm Post Mount forks. Although these are made by Avid, you can use these mounts for other calipers with the same mounting standard (74mm), such as Hayes.

The front IS 160mm adapter can also be used with a 140mm rotor on a frame with an IS rear mount